.\" $NetBSD: getusershell.3,v 1.6 1999/03/22 19:44:42 garbled Exp $
.\" $FreeBSD: src/lib/libc/gen/getusershell.3,v 1.10 2001/10/01 16:08:51 ru Exp $
.\"
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.\" @(#)getusershell.3 8.1 (Berkeley) 6/4/93
.\"
.Dd January 16, 1999
.Dt GETUSERSHELL 3
.Os
.Sh NAME
.Nm getusershell ,
.Nm setusershell ,
.Nm endusershell
.Nd get valid user shells
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In unistd.h
.Ft char *
.Fn getusershell void
.Ft void
.Fn setusershell void
.Ft void
.Fn endusershell void
.Sh DESCRIPTION
The
.Fn getusershell
function
returns a pointer to a valid user shell as defined by the
system manager in the shells database as described in
.Xr shells 5 .
If the shells database is not available,
.Fn getusershell
behaves as if
.Pa /bin/sh
and
.Pa /bin/csh
were listed.
.Pp
The
.Fn getusershell
function
reads the next
line (opening the file if necessary);
.Fn setusershell
rewinds the file;
.Fn endusershell
closes it.
.Sh FILES
.Bl -tag -width /etc/shells -compact
.It Pa /etc/shells
.El
.Sh DIAGNOSTICS
The routine
.Fn getusershell
returns a null pointer (0) on
.Dv EOF .
.Sh SEE ALSO
.Xr shells 5
.Sh HISTORY
The
.Fn getusershell
function appeared in
.Bx 4.3 .
.Sh BUGS
The
.Fn getusershell
function leaves its result in an internal static object and returns
a pointer to that object.
Subsequent calls to
.Fn getusershell
will modify the same object.